Question: At what point in time did Monaco have a population of 25809?
Paraphrase: What is the date that 25,809 people lived in Monaco?
SPARQL (Wikidata): SELECT ?value WHERE { wd:Q235 p:P1082 ?s . ?s ps:P1082 ?x filter(contains(?x , '25809.0')) . ?s pq:P585 ?value}